B0M0020
4. Diagnosis and Checking Procedure
Using Instruments
A: USING A CIRCUIT TESTER
1. VOLTAGE CHECK (range set to DC V)
Connect the positive probe to the terminal to be tested, and
the negative probe to body ground. (or the ground terminal of
the ECM)
B0M0021
2. CHECKING THE CONNECTION (range set toΩ)
Measure the resistance and check for open or shorted wire in
the harness or the connector.
NOTE:
This check must be carried out with both connectors discon-
nected.
(This avoids by-passing the connection through other cir-
cuits.)
1) Check for open circuit. (range:Ωx 1K)
Measure the resistance between the respective pins in both
connectors.
Specified resistance:
More than 1 MΩ(No continuity) Open circuit
Less than 10Ω(Continuity) O.K.
2) Check for correct insulation value. (range:Ωx 1K)
Measure the resistance between the pins in both connectors,
as well as between the suspected pin and the body. (body
short)
Specified resistance:
More than 1 MΩ(No continuity) O.K.
Less than 10Ω(Continuity) Short circuit
3) Resistance measurement (range set toΩ)
Measuring the internal resistance of sensors, solenoid valves
etc. to check the operating condition of components.
NOTE:
Select the appropriate range for measuring the internal
resistance, or the measurement will result in an incorrect
reading.
Before changing the measurement range the gauge must
be reset to zero.
9
[T4A2] FOREWORDFOREWORD
4. Diagnosis and Checking Procedure Using Instruments
